Transmission/reception device, transmission/reception method, and program

ABSTRACT

The present disclosure relates to a transmission/reception device, a transmission/reception method, and a program capable of improving a transmission characteristic in human body communication in both transmission and reception. The transmission/reception device used for human body communication includes three electrodes including a human body side electrode being in contact with a human body as a communication medium, a space side electrode provided on a space side, not a human body side, and a circuit board provided with a circuit. At this time, at the time of transmission, a switch between the space side electrode and the circuit board is turned off to make a three-pole electrode configuration having superiority in the transmission characteristic, and each electrode is caused to function as an independent electrode. On the other hand, at the time of reception, the switch between the space side electrode and the circuit board is turned on to electrically short-circuit the space side electrode and the circuit board, to cause the electrodes to function as a two-pole electrode configuration having superiority in the transmission characteristic. The present disclosure can be applied to a human body communication device.

TECHNICAL FIELD

The present disclosure relates to a transmission/reception device, atransmission/reception method, and a program, and in particular relatesto a transmission/reception device, a transmission/reception method, anda program capable of improving a transmission characteristic in humanbody communication.

BACKGROUND ART

Communication technology generally called human body communication via ahuman body communication network called a Body Area Network (BAN) isbecoming widespread (for example, see Patent Document 1).

The BAN is a wireless network assuming that information of a sensordisposed on the surface or the inside of a human body, or the like iswirelessly collected.

CITATION LIST Patent Document

-   Patent Document 1: Japanese Patent Application Laid-Open No.    2006-324774

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

By the way, an electrode configuration of a transmission/receptiondevice used for human body communication is roughly divided into atwo-pole configuration and a three-pole configuration.

In the two-pole configuration and the three-pole configuration,superiority of a transmission characteristic changes between time oftransmission and time of reception.

That is, at the time of transmission, the three-pole configuration ismore advantageous than the two-pole configuration, but at the time ofreception, the two-pole configuration is more advantageous than thethree-pole configuration.

The present disclosure has been made in view of such a situation, and inparticular to improve the transmission characteristic by having aconfiguration advantageous in the transmission characteristic at boththe time of transmission and the time of reception, in the configurationof the transmission/reception device in human body communication.

Solutions to Problems

An information processing device of an aspect of the present disclosureis a transmission/reception device including: a three-pole electrode tobe used at time of transmission of a signal using a human body as acommunication medium; a two-pole electrode to be used at time ofreception of the signal using the human body as the communicationmedium; and a switching unit performing switching to cause thethree-pole electrode to function at the time of transmission of thesignal and to cause the two-pole electrode to function at the time ofreception of the signal.

The switching unit can be caused to perform switching to cause thethree-pole electrode to function and to cause the two-pole electrode notto function, at the time of transmission of the signal, and performsswitching to cause the three-pole electrode not to function and to causethe two-pole electrode to function, at the time of reception of thesignal.

The three-pole electrode can be made to include an electrode connectedto one of transmission drivers each transmitting a signal bydifferential output and an electrode connected to another, and thetwo-pole electrode can be made to include an electrode connected to aninput of an amplification unit that amplifies a signal to be received.

The three-pole electrode and the two-pole electrode can be made toinclude: a human body side electrode to be in contact with a human bodybeing a communication medium; a space side electrode provided on a spaceside; and a circuit board Gnd having a Gnd pattern functioning as anelectrode of a circuit board provided with a circuit.

The three-pole electrode can be made to independently include the humanbody side electrode, the space side electrode, and the circuit boardGnd, and the two-pole electrode can be made to include the human bodyside electrode, and an electrode in which the space side electrode andthe circuit board Gnd are integrated together.

The switching unit can be made such that the switching unit switches thespace side electrode and the circuit board Gnd to be in electricallycontact or non-contact with each other, at the time of transmission, theswitching unit brings the space side electrode and the circuit board Gndinto an electrically non-contact state to make a three-pole electrodeconfiguration in which the human body side electrode, the space sideelectrode, and the circuit board Gnd are independent from each other, tocause the three-pole electrode to function, and at the time ofreception, the switching unit brings the space side electrode and thecircuit board Gnd into an electrically contact state to make anelectrode configuration in which the space side electrode and thecircuit board Gnd are integrated together, to make a configuration ofthe two-pole electrode, to cause the two-pole electrode to function.

A predetermined impedance can be provided between the human body sideelectrode and the space side electrode.

A transmission/reception method of an aspect of the present disclosureis a transmission/reception method of a transmission/reception deviceincluding: a three-pole electrode to be used at time of transmission ofa signal using a human body as a communication medium; and a two-poleelectrode to be used at time of reception of the signal using the humanbody as the communication medium, the transmission/reception methodincluding performing switching to cause the three-pole electrode tofunction at the time of transmission of the signal and to cause thetwo-pole electrode to function at the time of reception of the signal.

A program of an aspect of the present disclosure is a program thatcauses a computer, the computer controlling a transmission/receptiondevice including: a three-pole electrode to be used at time oftransmission of a signal using a human body as a communication medium;and a two-pole electrode to be used at time of reception of the signalusing the human body as the communication medium, to function as aswitching unit performing switching to cause the three-pole electrode tofunction at the time of transmission of the signal and to cause thetwo-pole electrode to function at the time of reception of the signal.

In an aspect of the present disclosure, switching is performed such thatat time of transmission of a signal using a human body as acommunication medium, a three-pole electrode functions, and at time ofreception of the signal using the human body as the communicationmedium, a two-pole electrode functions.

Effects of the Invention

According to an aspect of the present disclosure, it is possible toimprove the transmission characteristic at the time of transmission andreception in human body communication.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram for describing a configuration of a conventionaltransmission/reception device.

FIG. 2 is a diagram for describing a two-pole configuration and athree-pole configuration in the transmission/reception device of FIG. 1.

FIG. 3 is an exterior perspective view for describing an exterior of atransmission/reception device of the present disclosure.

FIG. 4 is a side cross-sectional view of the transmission/receptiondevice of FIG. 3.

FIG. 5 is a block diagram for describing an equivalent circuit of thetransmission/reception device of FIG. 3.

FIG. 6 is a diagram for describing operation at time of transmission ofthe transmission/reception device of FIG. 5.

FIG. 7 is a diagram for describing superiority over a two-poleconfiguration of a three-pole configuration at the time of transmissionin the transmission/reception device of FIG. 5.

FIG. 8 is a diagram for describing superiority over the three-poleconfiguration of the two-pole configuration at time of reception in thetransmission/reception device of FIG. 5.

FIG. 9 is a flowchart for describing transmission/reception processingby the transmission/reception device of FIG. 5.

FIG. 10 is a diagram for describing a first modification of thetransmission/reception device of FIG. 3.

FIG. 11 is a diagram for describing operation at the time oftransmission of the transmission/reception device of FIG. 10.

FIG. 12 is a diagram for describing operation at the time of receptionof the transmission/reception device of FIG. 10.

FIG. 13 is a diagram for describing a second modification of thetransmission/reception device of FIG. 3.

FIG. 14 is a diagram for describing operation at the time oftransmission of the transmission/reception device of FIG. 13.

FIG. 15 is a diagram for describing operation at the time of receptionof the transmission/reception device of FIG. 13.

FIG. 16 is a diagram for describing a configuration example of a generalpurpose personal computer.

MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of the present disclosure will be described indetail below with reference to the accompanying drawings. Incidentally,in the present specification and the drawings, constituents havingsubstantially the same functional configuration are denoted by the samereference signs, and redundant explanations are omitted.

<Communication System Using Conventional Human Body Communication>

FIG. 1 is a diagram illustrating a configuration example according to anembodiment of a communication system using human body communication towhich a technique of the present disclosure is applied.

In FIG. 1, a communication system 11 is configured by a transmissiondevice 31, a reception device 32, and a communication medium 33, and isa system in which the transmission device 31 and the reception device 32transmit and receive signals via the communication medium 33. That is,in the communication system 11, a signal transmitted from thetransmission device 31 is transmitted via the communication medium 33and received by the reception device 32.

The transmission device 31 includes a transmission reference electrode51, a transmission signal electrode 52, and a transmission unit 53. Thetransmission signal electrode 52 is one electrode of an electrode pairprovided for transmitting a signal to be transmitted via thecommunication medium 33, and is provided such that electrostaticcoupling to the communication medium 33 becomes stronger than that ofthe transmission reference electrode 51 that is the other electrode ofthe electrode pair. The transmission unit 53 is provided between thetransmission signal electrode 52 and the transmission referenceelectrode 51, and provides an electric signal (potential difference) tobe transmitted to the reception device 32 between these electrodes.

The reception device 32 includes a reception reference electrode 71, areception signal electrode 72, and a reception unit 73. The receptionsignal electrode 72 is one electrode of an electrode pair provided forreceiving a signal transmitted via the communication medium 33, and isprovided such that electrostatic coupling to the communication medium 33becomes stronger than that of the reception reference electrode 71 thatis the other electrode of the electrode pair. The reception unit 73 isprovided between the reception signal electrode 72 and the receptionreference electrode 71, detects an electric signal (potentialdifference) generated between these electrodes by the signal transmittedvia the communication medium 33, converts the electric signal into adesired electric signal, and restores the electric signal generated bythe transmission unit 53 of the transmission device 31.

The communication medium 33 is configured by a substance having aphysical characteristic capable of transmitting an electric signal, suchas a conductor, or a dielectric. For example, the communication medium33 is configured by a conductor typified by a metal such as copper,iron, or aluminum, a dielectric typified by pure water, rubber, glass orthe like, or a living body or the like that is a composite thereof, or amaterial having both a property as a conductor and a property as adielectric, like an electrolytic solution such as saline. In addition, ashape of the communication medium 33 may be any shape, and may be, forexample, a linear shape, a plate shape, a spherical shape, a prismaticshape, a cylindrical shape, or the like and may be any shape other thanthese shapes.

With this configuration, a weak current flows to the reception signalelectrode 72 of the reception device 32 from the transmission signalelectrode 52 of the transmission device 31 via the human body that isthe communication medium 33. A path through which this signal flows isreferred to as a human body side path.

In addition, the same amount of the signal current flowing from thetransmission device 31 to the reception device 32 via the human bodyside path returns from the reception device 32 to the transmissiondevice 31. The electric signal is transmitted by the transmissionreference electrode 51 by changing an electric field of a peripheralspace, from the reception reference electrode 71 provided at a positiondistant from the human body that is the communication medium 33. Thispath is referred to as a space side path.

<Configurations of Transmission Device and Reception Device>

Roughly two kinds of configurations are devised of the transmissiondevice 31 and the reception device 32, and one is a two-poleconfiguration as illustrated in the upper part of FIG. 2 and the otheris a three-pole configuration as illustrated in the lower part of FIG.2.

In the two-pole configuration, the transmission device 31 includes anelectrode configuring the transmission signal electrode 52 from thetransmission unit 53 that generates an electric signal, and an electrodecorresponding to the transmission reference electrode 51. In addition,in the two-pole configuration, the reception device 32 includes anelectrode configuring the reception signal electrode 72 from thereception unit 73 that receives an electric signal, and an electrodecorresponding to the reception reference electrode 71.

On the other hand, in the three-pole configuration, the transmissiondevice 31 includes an electrode including a circuit board 91, inaddition to the electrode configuring the transmission signal electrode52 from the transmission unit 53 that generates the electric signal, andthe electrode corresponding to the transmission reference electrode 51.In addition, the reception device 32 includes an electrode including acircuit board 101, in addition to the electrode configuring thereception signal electrode 72 from the reception unit 73 that receivesthe electric signal, and the electrode corresponding to the receptionreference electrode 71.

In the two-pole configuration and the three-pole configuration,communication characteristics are different from each other, andsuperiorities at the time of transmission and at the time of receptionare different from each other. That is, at the time of transmission, thethree-pole configuration has a more advantageous communicationcharacteristic than the two-pole configuration, but at the time ofreception, the two-pole configuration has a more advantageouscommunication characteristic than the three-pole configuration.

Therefore, if one of the configurations is adopted, the advantageouscommunication characteristic can be obtained either at the time oftransmission or at the time of reception, but at the same time, theadvantageous communication characteristic cannot be obtained at theother of the configurations.

<Configuration Example of Transmission/Reception Device of PresentDisclosure>

Therefore, in the transmission/reception device of the presentdisclosure, the device operates to have the three-pole configuration atthe time of transmission and operates to have the two-pole configurationat the time of reception.

FIG. 3 illustrates a configuration example of a transmission/receptiondevice 111 of the present disclosure that operates to have thethree-pole configuration at the time of transmission and operates tohave the two-pole configuration at the time of reception.

The transmission/reception device 111 of the present disclosure has, forexample, a disc-like exterior configuration, and the upper surface inthe upper left part of FIG. 3 is a space side electrode 121 that is notin contact with the communication medium 33 including a human body, andthe lower surface in the upper left part of FIG. 3 is a human body sideelectrode 122 that is in contact with the communication medium 33including the human body.

Further, as illustrated in a schematic cross-sectional view includingthe lower left part of FIG. 3, a circuit board 131 is provided betweenthe space side electrode 121 and the human body side electrode 122.Incidentally, the space side electrode 121, the human body sideelectrode 122, and the circuit board 131 are respectively thetransmission reference electrode 51, the transmission signal electrode52, and the circuit board 91 in the transmission device 31 of FIG. 2,and correspond to the reception reference electrode 71, the receptionsignal electrode 72, and the circuit board 101 in the reception device32.

For this reason, for example, as illustrated in the right part of FIG.3, the transmission/reception device 111 can also be caused to functionas a wearable terminal mounted to the human body by being attached to abelt 112 like a wristwatch. That is, in this case, in a case where thetransmission/reception device 111 is mounted using the belt 112, thehuman body side electrode 122 is brought into contact with an arm of thehuman body to which the belt 112 is mounted, and the space sideelectrode 121 that is the opposite side is exposed to a space.

<Detailed Configuration Example of Transmission/Reception Device>

Next, with reference to a side cross-sectional view of FIG. 4, adetailed configuration of the transmission/reception device 111 will bedescribed.

In FIG. 4, the human body that is the communication medium 33 is drawnin the lower part, and a side cross section is drawn in a state wherethe transmission/reception device 111 is disposed on the human body.

The space side electrode 121, a battery 132, the circuit board 131, andthe human body side electrode 122 are configured in this order from thetop.

On the circuit board 131, various board mounting components 131 a aremounted by being bonded with solder or the like. In FIG. 4, the battery132 that supplies electric power for driving the transmission/receptiondevice 111 is mounted on the back side of the surface of the circuitboard 131 on which the board mounting components 131 a are mounted (theupper side in the figure), and in FIG. 4, it is illustrated that thebattery 132 is electrically connected by wiring on the left part in thefigure.

In addition, the circuit board 131 is provided with constituentscorresponding to the above-described transmission unit 53 and receptionunit 73 by the board mounting components 131 a.

Further, in the circuit board 131, the transmission unit 53 and thereception unit 73 configured by the board mounting components 131 a areelectrically connected to the space side electrode 121 and the humanbody side electrode 122 by wiring.

Incidentally, the circuit board 131 usually has a wiring surface havinga multilayer structure. At least one entire surface of the wiringsurface having the multilayer structure is used as Gnd, and a Gndpattern is laid on the other surfaces, except for signal wiring. Inaddition, a direct current (DC) power supply is also wired with a thickline or is made into a pattern of a large area. The DC power supply isat the same potential as Gnd in terms of alternating current.Accordingly, the circuit board 131 can be regarded as an electrodehaving a Gnd potential in the entire surface. Therefore, in thefollowing, the circuit board 131 is also referred to as the circuitboard electrode (circuit board Gnd) 131.

<Function Achieved by Transmission/Reception Device of FIG. 4>

With reference to a functional block diagram of FIG. 5, a functionachieved by the transmission/reception device 111 of FIG. 4 will bedescribed.

The transmission/reception device 111 includes the space side electrode121, the human body side electrode 122, the circuit board (circuit boardelectrode (circuit board Gnd)) 131, an output driver 141, a receptioninput amplifier (Amplifier) 142, and a switch (SW) 143.

The output driver (TX) 141 uses the space side electrode 121, the humanbody side electrode 122, and the circuit board 131 to output atransmission signal from the space side path and the human body sidepath by differential output.

The reception input amplifier (RX) 142 uses the space side electrode121, the human body side electrode 122, and the circuit board 131 toreceive a reception signal from the space side path and the human bodyside path, and amplifies and outputs the signal.

The switch (SW) 143 electrically connects/insulates the space sideelectrode 121 to/from the circuit board 131. More specifically, theswitch 143 is turned off at the time of transmission to insulate thespace side electrode 121 from the circuit board 131, and thetransmission/reception device 111 is made to have the three-poleconfiguration of the space side electrode 121, the human body sideelectrode 122, and the circuit board 131. In addition, the switch 143 isturned on at the time of reception to electrically connects the spaceside electrode 121 to the circuit board 131, and thetransmission/reception device 111 is made to have the two-poleconfiguration of the human body side electrode 122 and an electrode inwhich the space side electrode 121 and the circuit board 131 areintegrated together.

By performing switching to turn on or off the switch 143, thetransmission/reception device 111 is switched to either the three-poleconfiguration or the two-pole configuration, and the transmissioncharacteristic becomes superior at each of the time of transmission andthe time of reception.

<Operation of Three-Pole Configuration at Time of Transmission>

Next, with reference to FIG. 6, operation of the three-poleconfiguration at the time of transmission will be described.

The upper central part of FIG. 6 illustrates a side cross section inwhich only constituents of the space side electrode 121, the human bodyside electrode 122, and the circuit board 131 are extracted. Inaddition, the lower central part of FIG. 6 illustrates an equivalentcircuit of the constituents of the upper central part of FIG. 6. Thatis, a transmission driver 141 a is provided between the space sideelectrode 121 and the circuit board 131, and a transmission driver 141 bis provided between the human body side electrode 122 and the circuitboard 131.

As illustrated in the lower left part of FIG. 6, the transmissiondrivers 141 a and 141 b are drivers respectively having differentpolarities when the circuit board 131 is set to the ground Gnd.Therefore, as illustrated in the upper left part of FIG. 6, each outputsignal has a waveform of the same voltage v in opposite phase, and thesignal becomes the differential output. Incidentally, in the upper leftpart of FIG. 6, a potential of the space side electrode 121, a potentialof the circuit board 131 that is the ground Gnd, and a potential of thehuman body side electrode 122 are illustrated from the top.

Because of this configuration, when the human body side that is thetransmission medium 33 is regarded as a reference voltage, the potentialof the circuit board 131 and the potential of the space side electrode121 have the same phase as illustrated in the lower right part of FIG.6. Further, as illustrated in the upper right part of FIG. 6, thepotential of the space side electrode 121 is a doubled voltage 2v ascompared with the case of the upper left part of FIG. 6, and thetransmission characteristic at the time of transmission becomessuperior.

<Superiority Over Two-Pole Configuration of Three-Pole Configuration atTime of Transmission>

Next, superiority over the two-pole configuration of the three-poleconfiguration at the time of transmission will be described.

In a case where the space side electrode 121, the human body sideelectrode 122, and the circuit board 131 are made into the two-poleconfiguration, three kinds of configurations are conceivable.

That is, three kinds of examples are conceivable, the examples being anexample of a configuration only by the circuit board 131 and the humanbody side electrode 122 as illustrated in the upper right part of FIG.7, an example of a configuration only by the circuit board 131 and thespace side electrode 121 as illustrated in the middle right part of FIG.7, and an example in which the switch 143 is turned on to make oneelectrode in which the circuit board 131 and the space side electrode121 are short-circuited, and further the two-pole configuration is madeby the one electrode and the human body side electrode 122, asillustrated in the lower right part of FIG. 7.

However, in both the upper right part and the middle right part, anelectrode area decreases and the maximum output voltage also remains atv, as compared with the three-pole configuration. In addition, in thelower right part, the electrode area is the same as the three-poleconfiguration, but the maximum output voltage remains at v.

Therefore, in either case, as illustrated in the left part of FIG. 7,the three-pole configuration is superior to the two-pole configuration,at the time of transmission.

<Superiority Over Three-Pole Configuration of Two-Pole Configuration atTime of Reception>

Next, superiority over the three-pole configuration of the two-poleconfiguration at the time of reception will be described.

As illustrated in the left part of FIG. 8, an impedance from the circuitboard 131 that is the ground Gnd of the space side electrode 121 thatinputs a signal to the positive input terminal of the reception inputamplifier 142 and an impedance from the circuit board 131 that is theground Gnd of the human body side electrode 122 that inputs a signal tothe negative input terminal of the reception input amplifier 142 areequal (=z/2) to each other.

At this time, in a case of the three-pole configuration in which theswitch 143 is turned off and the circuit board (circuit board electrode)131 and the space side electrode 121 are independent from each other, animpedance between the circuit board 131 and the human body sideelectrode 122 is a half (=z/2) of an impedance between the space sideelectrode 121 and the human body side electrode 122.

On the other hand, in a case of the two-pole configuration in which theswitch 143 is turned on and the circuit board (circuit board electrode)131 and the space side electrode 121 are short-circuited, the impedancebetween the circuit board 131 and the human body side electrode 122 isthe same impedance (=z) as the impedance between the space sideelectrode 121 and the human body side electrode 122.

An impedance of the space side path is capacitance between thetransmission and reception electrodes. Since a reception signal level isdetermined by a ratio of an input impedance of the reception device toan impedance of the space path, by which the transmission signal isattenuated, the reception signal is increased substantially proportionalto an increase in the input impedance.

With this configuration, as illustrated by a waveform (an image of awaveform level when nothing is connected to the electrode), thepotential of the circuit board 131 in the two-pole configuration istwice the potential in the three-pole configuration.

As a result, an input voltage to the positive input terminal of thereception input amplifier 142 becomes higher in the two-poleconfiguration than in the three-pole configuration, so that receptionsensitivity can be improved.

<Transmission/Reception Processing>

Next, with reference to a flowchart of FIG. 9, transmission/receptionprocessing of the transmission/reception device 111 of FIG. 5 will bedescribed.

In step S11, the circuit board 131 determines whether or not it is thetime of transmission. In step S11, in a case where it is determined thatit is the time of transmission, the processing proceeds to step S12.

In step S12, the circuit board 131 performs control to turn off theswitch 143, so that the space side electrode 121 and the circuit board131 are made to be independent electrodes, whereby thetransmission/reception device 111 is caused to function as thethree-pole configuration. With this operation, thetransmission/reception device 111 is caused to function as thethree-pole configuration having superiority at the time of transmission.With this operation, it becomes possible to cause thetransmission/reception device 111 to function as the three-poleconfiguration having superiority at the time of transmission.

Incidentally, in step S11, in a case where it is determined that it isnot the time of transmission, the processing in step S12 is skipped.

In step S13, the circuit board 131 determines whether or not it is thetime of reception. In step S13, in a case where it is determined that itis the time of reception, the processing proceeds to step S14.

In step S14, the circuit board 131 performs control to turn on theswitch 143, so that the space side electrode 121 and the circuit board131 are made into an integrated electrode, whereby thetransmission/reception device 111 is caused to function as the two-poleconfiguration. With this operation, it becomes possible to cause thetransmission/reception device 111 to function as the two-poleconfiguration having superiority at the time of reception.

Incidentally, in step S13, in a case where it is determined that it isnot the time of reception, the processing in step S14 is skipped.

In step S15, the circuit board 131 determines whether or not theprocessing is ended, and in a case where the processing is not ended,the processing returns to step S11 and the processing of the step S11and subsequent steps is repeated. Then, in step S15, in a case where itis determined that the processing is ended, the processing is ended.

With the above processing, by adopting the three-pole configurationhaving superiority at the time of transmission, and adopting thetwo-pole configuration having superiority at the time of reception, itis possible to improve the transmission characteristic at each of thetime of transmission and the time of reception.

<First Modification>

The transmission/reception device 111 is an example of a configurationin which the two-pole configuration and the three-pole configuration canbe switched by performing switching to turn on or off the switch;however, another configuration may be used as long as the configurationcan perform switching between the two-pole configuration and thethree-pole configuration, and for example, a configuration asillustrated in FIG. 10 may be adopted.

Incidentally, in the configuration of the transmission/reception device111 of FIG. 10, constituents having the same functions as those of thetransmission/reception device 111 of FIG. 5 are denoted by the samereference signs and the same names, and descriptions thereof will beomitted as appropriate.

That is, the circuit board 131 of FIG. 10 is configured by a Large ScaleIntegration (LSI) 150. The LSI 150 includes the drivers 141 a and 141 b,the reception input amplifier (Low Noise Amplifier (LNA)) 142, switches(SW) 151 to 153, a transmission signal processing unit 161, and areception signal processing unit 162.

The transmission signal processing unit 161 controls the drivers 141 aand 141 b and the switches (SW) 151 to 153 to transmit the transmissionsignal in the three-pole configuration of the space side electrode 121,the circuit board 131, and the human body side electrode 122.

The switch 151 switches an electrical connection between the driver 141a and the space side electrode 121. The switch 152 switches anelectrical connection between the driver 141 b and the human body sideelectrode 122. The switch 153 switches whether or not to set the spaceside electrode 121 of the reception input amplifier 142 to the groundpotential (GND) that is the potential of the circuit board 131.

An impedance (=z) 154 is provided between potentials of the space sideelectrode 121 of the reception input amplifier 142 and an input terminalof the human body side electrode 122. The reception signal processingunit 162 performs signal processing on an output signal of the receptioninput amplifier 142.

At the time of transmission, as illustrated in FIG. 11, the switches 151and 152 are turned on and the switch 153 is turned off, so that a pathindicated by a thick line in the figure is electrified, and the signaloutput from the transmission signal processing unit 161 is transmittedin the three-pole configuration including the space side electrode 121,the circuit board 131, and the human body side electrode 122.

On the other hand, at the time of reception, as illustrated in FIG. 12,the switches 151 and 152 are turned off and the switch 153 is turned on,so that a path indicated by a thick line in the figure is electrified,and the space side electrode 121 and the circuit board 131 areconfigured as an integrated electrode, and a signal transmitted isreceived in the two-pole configuration together with the human body sideelectrode 122, and a signal output from the reception input amplifier142 in accordance with the reception signal is processed by thereception signal processing unit 162.

As described above, also in the transmission/reception device 111 ofFIG. 10, the three-pole configuration is made at the time oftransmission and the two-pole configuration is made at the time ofreception, so that an enhanced transmission characteristic can beobtained at both the time of transmission and the time of reception.

Incidentally, transmission/reception processing in thetransmission/reception device 111 of FIG. 10 is the same as theprocessing described with reference to the flowchart of FIG. 9, so thatthe description thereof will be omitted. However, switching between thethree-pole configuration and the two-pole configuration is performed byoperation of the switches 151 to 153, instead of the switch 143. Thatis, at the time of transmission, the switches 151 and 152 are turned onand the switch 153 is turned off to make the three-pole configuration,and at the time of reception, the switches 151 and 152 are turned offand the switch 153 is turned on to make the two-pole configuration.

<Second Modification>

In addition, the transmission/reception device 111 may have aconfiguration as illustrated in FIG. 13 below, for example.

Incidentally, in the configuration of the transmission/reception device111 of FIG. 13, constituents having the same functions as those of thetransmission/reception device 111 of FIG. 10 are denoted by the samereference signs and the same names, and descriptions thereof will beomitted as appropriate.

That is, the transmission/reception device 111 of FIG. 13 differs fromthe transmission/reception device 111 of FIG. 10 in that a switch 171 isprovided instead of the switch 153, and the impedance (=z) 154 isprovided between the input terminal from the human body side electrode122 of the reception input amplifier 142 and the circuit board 131.

That is, the switch 171 switches whether or not to ground the space sideelectrode 121 onto the circuit board 131. By turning off the switches151 and 152 and turning on the switch 171, the space side electrode 121is grounded onto the circuit board 131, whereby the space side electrode121 and the circuit board 131 are integrated together, and arelationship of the impedance 154 is established to the human body sideelectrode 122, so that the two-pole configuration is made.

Conversely, by turning off the switch 171 and turning on the switches151 and 152, the three-pole configuration is made similarly to thetransmission/reception device 111 in FIG. 10.

That is, at the time of transmission, as illustrated in FIG. 14, theswitches 151 and 152 are turned on and the switch 171 is turned off, sothat a path indicated by a thick line in the figure is electrified, andthe signal output from the transmission signal processing unit 161 istransmitted in the three-pole configuration including the space sideelectrode 121, the circuit board 131, and the human body side electrode122.

On the other hand, at the time of reception, as illustrated in FIG. 15,the switches 151 and 152 are turned off and the switch 171 is turned on,so that a path indicated by a thick line in the figure is electrified,and the space side electrode 121 and the circuit board 131 areconfigured as an integrated electrode, and a signal transmitted isreceived in the two-pole configuration together with the human body sideelectrode 122, and a signal output from the reception input amplifier142 in accordance with the reception signal is processed by thereception signal processing unit 162.

As described above, also in the transmission/reception device 111 ofFIG. 13, the three-pole configuration is made at the time oftransmission and the two-pole configuration is made at the time ofreception, so that an enhanced transmission characteristic can beobtained at both the time of transmission and the time of reception.

Incidentally, transmission/reception processing in thetransmission/reception device 111 of FIG. 13 is also the same as theprocessing described with reference to the flowchart of FIG. 9, so thatthe description thereof will be omitted. However, switching between thethree-pole configuration and the two-pole configuration is performed byoperation of the switches 151, 152, and 171, instead of the switch 143.That is, at the time of transmission, the switches 151 and 152 areturned on and the switch 171 is turned off to make the three-poleconfiguration, and at the time of reception, the switches 151 and 152are turned off and the switch 171 is turned on to make the two-poleconfiguration.

In addition, in the above-described transmission/reception device 111,an example has been described of switching to one of two states, onestate in which the three-pole configuration and the two-poleconfiguration are switched by turning on or off the switch and thetransmission/reception device 111 is caused to function as thethree-pole configuration and not to function as the two-poleconfiguration, and the other state in which the transmission/receptiondevice 111 is caused to function as the two-pole configuration and notto function as the three-pole configuration; however, a three-poleconfiguration electrode and a two-pole configuration electrode may beindividually configured physically, and the three-pole configurationelectrode may be used at the time of transmission, and the two-poleconfiguration electrode may be used at the time of reception.

Further, a transmission processing block including a transmission signalprocessing unit and the three-pole configuration electrode, and atransmission processing block including a reception signal processingunit and the two-pole configuration electrode may be individuallyprovided and operated at the same time.

As described above, according to the transmission/reception device inhuman body communication of the present disclosure, it is possible toperform transmission and reception with an enhanced transmissioncharacteristic at the time of transmission and the time of reception.

<Example of Execution by Software>

By the way, a series of the processing described above can be executedby hardware; however, it can also be executed by software. In a casewhere the series of the processing is executed by the software, aprogram configuring the software is installed from a recording medium toa computer incorporated in dedicated hardware, or, for example, ageneral purpose personal computer or the like capable of executingvarious functions by installing various programs.

FIG. 16 illustrates a configuration example of a general purposepersonal computer. The personal computer incorporates a CentralProcessing Unit (CPU) 1001. The CPU 1001 is connected to an input/outputinterface 1005 via a bus 1004. The bus 1004 is connected to Read OnlyMemory (ROM) 1002 and Random Access Memory (RAM) 1003.

The input/output interface 1005 is connected to an input unit 1006including input devices such as a keyboard and a mouse for a user toinput an operation command, an output unit 1007 for outputting to adisplay device a processing operation screen and an image of aprocessing result, a storage unit 1008 including a hard disk drive andthe like for storing programs and various data, and a communication unit1009 including a Local Area Network (LAN) adapter and the like forexecuting communication processing via a network typified by theInternet. In addition, a drive 1010 is connected for reading data fromand writing data to a removable medium 1011 such as a magnetic disk(including flexible disk), an optical disk (including Compact Disc-ReadOnly Memory (CD-ROM) and a Digital Versatile Disc (DVD)), a magnetooptical disk (including Mini Disc (MD)), or a semiconductor memory.

The CPU 1001 executes various types of processing in accordance with aprogram stored in the ROM 1002, or a program read from the removablemedium 1011, such as the magnetic disk, the optical disk, the magnetooptical disk, or the semiconductor memory, to be installed to thestorage unit 1008, and loaded to the RAM 1003 from the storage unit1008. In the RAM 1003, data necessary for the CPU 1001 to execute thevarious types of processing or the like is also stored appropriately.

In the computer configured as described above, for example, the CPU 1001loads the program stored in the storage unit 1008 to the RAM 1003 viathe input/output interface 1005 and the bus 1004 to execute the seriesof processing described above.

The program executed by the computer (CPU 1001) can be provided, forexample, by being recorded in the removable medium 1011 as a packagemedium or the like. In addition, the program can be provided via a wiredor wireless transmission medium such as a local area network, theInternet, or digital satellite broadcasting.

In the computer, the program can be installed to the storage unit 1008via the input/output interface 1005 by mounting the removable medium1011 to the drive 1010. In addition, the program can be installed to thestorage unit 1008 by receiving with the communication unit 1009 via thewired or wireless transmission medium. Further, the program can beinstalled in advance to the ROM 1002 and the storage unit 1008.

Incidentally, the program executed by the computer can be a program bywhich the processing is performed in time series along the orderdescribed herein, and can be a program by which the processing isperformed in parallel or at necessary timing such as when a call isperformed.

In addition, herein, a system means an aggregation of a plurality ofconstituents (apparatus, module (component), and the like), and it doesnot matter whether or not all of the constituents are in the samecabinet. Therefore, a plurality of apparatuses that is accommodated in aseparate cabinet and connected to each other via a network and oneapparatus that accommodates a plurality of modules in one cabinet areboth systems.

Incidentally, the embodiment of the present disclosure is not limited tothe embodiments described above, and various modifications are possiblewithout departing from the scope of the present disclosure.

For example, the present disclosure can adopt a configuration of cloudcomputing that shares one function in a plurality of apparatuses via anetwork to process in cooperation.

In addition, each step described in the above flowchart can be executedby sharing in a plurality of apparatuses, other than being executed byone apparatus.

Further, in a case where a plurality of pieces of processing is includedin one step, the plurality of pieces of processing included in the onestep can be executed by sharing in a plurality of apparatuses, otherthan being executed by one apparatus.

Incidentally, the present disclosure can also adopt the followingconfigurations.

<1> A transmission/reception device including:

a three-pole electrode to be used at time of transmission of a signalusing a human body as a communication medium;

a two-pole electrode to be used at time of reception of the signal usingthe human body as the communication medium; and

a switching unit performing switching to cause the three-pole electrodeto function at the time of transmission of the signal and to cause thetwo-pole electrode to function at the time of reception of the signal.

<2> The transmission/reception device according to <1>, in which

the switching unit performs switching to cause the three-pole electrodeto function and to cause the two-pole electrode not to function, at thetime of transmission of the signal, and performs switching to cause thethree-pole electrode not to function and to cause the two-pole electrodeto function, at the time of reception of the signal.

<3> The transmission/reception device according to <1>, in which

the three-pole electrode includes an electrode connected to one oftransmission drivers each transmitting a signal by differential outputand an electrode connected to another, and

the two-pole electrode includes an electrode connected to an input of anamplification unit that amplifies a signal to be received.

<4> The transmission/reception device according to <1>, in which

the three-pole electrode and the two-pole electrode include:

a human body side electrode to be in contact with a human body being acommunication medium;

a space side electrode provided on a space side; and

a circuit board Gnd having a Gnd pattern functioning as an electrode ofa circuit board provided with a circuit.

<5> The transmission/reception device according to <4>, in which

the three-pole electrode independently includes the human body sideelectrode, the space side electrode, and the circuit board Gnd, and

the two-pole electrode includes the human body side electrode, and anelectrode in which the space side electrode and the circuit board Gndare integrated together.

<6> The transmission/reception device according to <5>, in which

the switching unit switches the space side electrode and the circuitboard Gnd to be in electrically contact or non-contact with each other,

at the time of transmission, the switching unit brings the space sideelectrode and the circuit board Gnd into an electrically non-contactstate to make a three-pole electrode configuration in which the humanbody side electrode, the space side electrode, and the circuit board Gndare independent from each other, to cause the three-pole electrode tofunction, and

at the time of reception, the switching unit brings the space sideelectrode and the circuit board Gnd into an electrically contact stateto make an electrode configuration in which the space side electrode andthe circuit board Gnd are integrated together, to make a configurationof the two-pole electrode, to cause the two-pole electrode to function.

<7> The transmission/reception device according to <4>, in which

a predetermined impedance is provided between the human body sideelectrode and the space side electrode.

<8> A transmission/reception method of a transmission/reception deviceincluding:

a three-pole electrode to be used at time of transmission of a signalusing a human body as a communication medium; and

a two-pole electrode to be used at time of reception of the signal usingthe human body as the communication medium,

the transmission/reception method including

performing switching to cause the three-pole electrode to function atthe time of transmission of the signal and to cause the two-poleelectrode to function at the time of reception of the signal.

<9> A program that causes a computer,

the computer controlling a transmission/reception device including:

a three-pole electrode to be used at time of transmission of a signalusing a human body as a communication medium; and

a two-pole electrode to be used at time of reception of the signal usingthe human body as the communication medium,

to function as a switching unit performing switching to cause thethree-pole electrode to function at the time of transmission of thesignal and to cause the two-pole electrode to function at the time ofreception of the signal.

REFERENCE SIGNS LIST

-   33 Communication medium (human body)-   111 Transmission/reception device-   112 Belt-   121 Space side electrode-   122 Human body side electrode-   131 Circuit board-   132 Battery-   141, 141 a, 141 b Output driver-   142 Reception input amplifier-   143 Switch-   151 to 153 Switch-   154 Impedance-   161 Transmission signal processing unit-   162 Reception signal processing unit-   171 Switch

1. A transmission/reception device comprising: a three-pole electrode tobe used at time of transmission of a signal using a human body as acommunication medium; a two-pole electrode to be used at time ofreception of the signal using the human body as the communicationmedium; and a switching unit performing switching to cause thethree-pole electrode to function at the time of transmission of thesignal and to cause the two-pole electrode to function at the time ofreception of the signal.
 2. The transmission/reception device accordingto claim 1, wherein the switching unit performs switching to cause thethree-pole electrode to function and to cause the two-pole electrode notto function, at the time of transmission of the signal, and performsswitching to cause the three-pole electrode not to function and to causethe two-pole electrode to function, at the time of reception of thesignal.
 3. The transmission/reception device according to claim 1,wherein the three-pole electrode includes an electrode connected to oneof transmission drivers each transmitting a signal by differentialoutput and an electrode connected to another, and the two-pole electrodeincludes an electrode connected to an input of an amplification unitthat amplifies a signal to be received.
 4. The transmission/receptiondevice according to claim 1, wherein the three-pole electrode and thetwo-pole electrode include: a human body side electrode to be in contactwith a human body being a communication medium; a space side electrodeprovided on a space side; and a circuit board Gnd having a Gnd patternfunctioning as an electrode of a circuit board provided with a circuit.5. The transmission/reception device according to claim 4, wherein thethree-pole electrode independently includes the human body sideelectrode, the space side electrode, and the circuit board Gnd, and thetwo-pole electrode includes the human body side electrode, and anelectrode in which the space side electrode and the circuit board Gndare integrated together.
 6. The transmission/reception device accordingto claim 5, wherein the switching unit switches the space side electrodeand the circuit board Gnd to be in electrically contact or non-contactwith each other, at the time of transmission, the switching unit bringsthe space side electrode and the circuit board Gnd into an electricallynon-contact state to make a three-pole electrode configuration in whichthe human body side electrode, the space side electrode, and the circuitboard Gnd are independent from each other, to cause the three-poleelectrode to function, and at the time of reception, the switching unitbrings the space side electrode and the circuit board Gnd into anelectrically contact state to make an electrode configuration in whichthe space side electrode and the circuit board Gnd are integratedtogether, to make a configuration of the two-pole electrode, to causethe two-pole electrode to function.
 7. The transmission/reception deviceaccording to claim 4, wherein a predetermined impedance is providedbetween the human body side electrode and the space side electrode.
 8. Atransmission/reception method of a transmission/reception deviceincluding: a three-pole electrode to be used at time of transmission ofa signal using a human body as a communication medium; and a two-poleelectrode to be used at time of reception of the signal using the humanbody as the communication medium, the transmission/reception methodcomprising performing switching to cause the three-pole electrode tofunction at the time of transmission of the signal and to cause thetwo-pole electrode to function at the time of reception of the signal.9. A program that causes a computer, the computer controlling atransmission/reception device including: a three-pole electrode to beused at time of transmission of a signal using a human body as acommunication medium; and a two-pole electrode to be used at time ofreception of the signal using the human body as the communicationmedium, to function as a switching unit performing switching to causethe three-pole electrode to function at the time of transmission of thesignal and to cause the two-pole electrode to function at the time ofreception of the signal.